JPH10163594A - Electronic circuit board and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the occurrence of cracks at an interface between a conductive film and a glass fiber by mixing electric insulating filler having high thermal conductivity into a void of an inner surface of the film, and filling high thermal conductive resin having low thermal expansion characteristic equivalent to that of the film, and adhering the resin to the film. SOLUTION: A resin board 201 is obtained by integrally laminating a high thermal conductive resin layer 205 mixed with electric insulating filler having high thermal conductivity at both surfaces of a core material 204 made of fiber-reinforced resin. A void 202 at an inner surface of a conductive film 203 is charged with a high thermal conductive resin having low thermal expansion characteristics, equivalent to or lower than a metal of the film, sealed. Further, one or multilayer wiring circuits 208 are laminated integrally via an insulating layer 207 on the circuit 206, and the laminated circuit 208 are laminated on the sealed void 202. As a result, a problem of cracks in the film and warping of the board is solved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic circuit board which is excellent in heat removal, heat diffusion, crack prevention of a conductive film on the inner surface of a via hole, and waterproofness, and a method of manufacturing such a board at low cost. It is.

[0002]

2. Description of the Related Art In recent years, the density of semiconductors has been increased, and the multilayer structure of electronic circuit boards has been a worldwide trend. As a result, the number of via holes for conducting between the upper and lower surfaces of the substrate has been greatly increased. At present, resin materials such as so-called glass-epoxy, phenolic resin, BT resin, and polyimide resin in which glass fiber, kepra fiber, or metal fiber are mixed with epoxy resin, bismald, imide resin, and the like are generally used as substrate materials. A metal substrate is appropriately laminated on these resin substrates as necessary, or a different resin substrate is appropriately laminated on the resin substrate as necessary.The thermal expansion in the thickness direction of these resin substrates is used. The coefficients generally reach (60-100) × 10 ⁻⁶ . The metal film of the via hole conductive film is 17-18x even with the largest copper film.
The thermal expansion characteristic is about 10 ⁻⁶ , which is extremely different from that of the substrate material. -60 ° C x in the test items of semiconductor reliability
There is a thermal fatigue test in which a heat sile is repeated for 30 minutes to 155 ° C. for 30 minutes. Can not follow enough. As a result, a tensile thermal stress acts on the conductive film, cracks are generated, electric characteristics are deteriorated, water is absorbed, and popcorn is generated during reflow soldering. In addition, cracks also occur at the interface of the glass fibers inside the substrate, and water enters in the PCT test. Further, the substrate itself is warped. On the other hand, the recent trend of electronic circuit boards is that the use of a high current increases the heat generated at the junction of the chip, and it is important to spread and dissipate the heat in order not to overheat this part. At present, a heat sink or a heat spreader is attached to the lower surface of the chip to diffuse and dissipate heat, but the attachment of the heat sink or the heat spreader increases the cost of the entire substrate. It is preferable that the heat sink and the heat spreader are reduced or omitted as much as possible.
On the other hand, conventional electronic circuit boards have holes in the via holes, so when wiring circuits are stacked, it is necessary to avoid these holes and stack them. There are disadvantages that cannot be done. How to place a wiring circuit on a via hole is a very important issue in increasing the density.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object the following problems of cracks due to thermal fatigue, problems of water intrusion,
A new structure of an electronic circuit board and a method of manufacturing the same that can simultaneously solve the problem of substrate warpage, the problem of cost increase by using a heat sink and a heat spreader, and the problem of higher density of wiring circuits. It is.

[0004]

Means for Solving the Problems The present inventor has made intensive studies on the above problems and obtained the following findings. That is, 1. In an electronic circuit board in which a conductive film is formed on an inner surface of a via hole penetrating an insulating base material, the structure of the insulating base material is mixed with a high thermal conductive and electrically insulating filler on both surfaces of a core material made of fiber reinforced resin. A high thermal conductive resin layer is laminated and integrated, and pores on the inner surface of the conductive film are mixed with an electrically insulating filler having high thermal conductivity, and have a low thermal expansion characteristic equal to or less than that of the metal of the conductive film. By filling the high thermal conductive resin with the resin and bonding the conductive film to the conductive resin, the problem of cracks in the conductive film, cracks at the glass fiber interface, and warpage of the substrate can be solved. Diffusion and heat dissipation are significantly improved, resulting in heat sink,
It has been found that the heat spreader can be omitted completely or widely. Also, 2. In an electronic circuit board in which a wiring circuit is laminated and integrated on both surfaces of a resin substrate and a conductive film is formed on an inner surface of a via hole penetrating the substrate in order to make the wiring circuits on both surfaces conductive, holes on the inner surface of the conductive film Is filled with a high thermal conductive resin having a high thermal conductivity and an electrically insulating filler mixed with an electrically insulating filler, and having a low thermal expansion characteristic equal to or less than that of the metal of the conductive film, and sealing, and Even if one or more multilayer wiring circuits are laminated and integrated on the wiring circuit with an insulating layer interposed therebetween, and the laminated circuit is deposited on the sealed hole, Because the expansion coefficient can be smaller than that of copper circuit, it has excellent adhesion to the circuit,
In addition, they have found that they can be stacked at a high density. At this time, it was also found that the problem of cracks in the conductive film, the cracks in the glass fiber interface, the problem of substrate warpage, the problem of heat diffusion, and the problem of heat dissipation can be solved at the same time. Also, 3. A wiring circuit is laminated and integrated on both sides of the resin substrate, and in an electronic circuit board in which a conductive film is formed on an inner surface of a via hole penetrating the substrate to make the wiring circuits on both sides conductive, the structure of the resin substrate is A high thermal conductive resin layer mixed with a high thermal conductive and electrically insulating filler is laminated and integrated on both sides of a core material made of fiber reinforced resin, and the holes on the inner surface of the conductive film are electrically insulated with high thermal conductivity. Filled with a high thermal conductive resin having a low thermal expansion property equal to or less than the metal of the conductive film, mixed with a conductive filler, and sealed, and further an insulating layer is sandwiched on the wiring circuit. Then, one or more wiring circuits are laminated and integrated, and the laminated circuit is deposited on the sealed hole portion.
The problem of cracks in the conductive film, cracks in the glass fiber interface,
The problem of substrate warpage and the problem of high-density lamination of wiring circuits have been solved, and the heat diffusion and heat dissipation of the substrate have been significantly improved. As a result, the heat sink and heat spreader can be omitted completely or largely. I started. Also, 4. One or more ceramic fillers selected from among (aluminum nitride, silicon carbide, magnesia, and alumina) are particularly preferable as the high thermal conductive and electrically insulating filler. Also, 5. The amount of the filler in the high thermal conductive resin layer is 20 to
The range of 85% by weight is particularly preferable. And 6. The amount of the filler in the filling resin is 20 to 85 w
The range of t% is preferable. And 7. The high thermal conductive resin layer is most preferably a film of a high thermal conductive resin. 8. A new method of manufacturing a multilayer electronic circuit board that can solve the problem of mounting wiring circuits on via holes and the problem of reducing or eliminating heat sinks and heat spreaders. The present invention has been made based on the above findings, and has the following configuration.

(1) In an electronic circuit board having a conductive film <103> formed on an inner surface of a via hole <102> penetrating an insulating base material <101>, the insulating base material <101> is a core made of fiber reinforced resin. High thermal conductive resin layer in which high thermal conductive and electrically insulating filler is mixed on both sides of material <104>
105> has a laminated and integrated structure, and the conductive film <
103> inner pores <102> are filled with a high thermal conductive resin having a high thermal conductivity and an electrically insulating filler mixed therein and having a low thermal expansion characteristic equal to or less than that of the metal of the conductive film <103>; An electronic circuit board, wherein the filling resin and the conductive film are bonded. (See Fig. 1)

(2) Wiring circuits <206> are laminated and integrated on both sides of the resin substrate <201>, and the wiring circuits <2> on both sides are integrated.
In the electronic circuit board having a conductive film <203> formed on an inner surface of a via hole <202> penetrating the substrate <201> to make the conductive film 06> conductive, a hole <202> on the inner surface of the conductive film <203> is formed. An electrically insulating material mixed with an electrically insulating filler having a high thermal conductivity, and the conductive film <203>
And filled with a high thermal conductive resin having a low thermal expansion property equal to or less than the metal of
6>, an insulating layer <207> is interposed therebetween to further integrate a single-layer or multilayer wiring circuit <208>, and the laminated circuit <208> is placed on the sealed hole portion <202>. An electronic circuit board characterized by being deposited. (See FIG. 2).

(3) A wiring circuit <206> is laminated and integrated on both sides of the resin substrate <201>, and the wiring circuits <2>
06>, an electronic circuit board having a conductive film <203> formed on the inner surface of a via hole <202> penetrating through the substrate <201> to conduct the resin substrate <201>.
Has a structure in which a high thermal conductive resin layer <205> in which a high thermal conductive and electrically insulating filler is mixed is laminated and integrated on both surfaces of a core material <204> made of a fiber reinforced resin, and the conductive film <203>> The pores <202> on the inner surface are filled with a high thermal conductive resin having high thermal conductivity, an electrically insulating filler mixed with an electrically insulating filler, and having a low thermal expansion property equal to or lower than that of the metal of the conductive film. And the wiring circuit is <2
06>, an insulating layer <207> is interposed therebetween, and a one-layer or multi-layer wiring circuit <208> is laminated and integrated, and the laminated circuit <208> is placed on the sealed hole portion <202>. An electronic circuit board characterized by being deposited. (See FIG. 2).

(4) The high thermal conductive and electrically insulating filler comprises (aluminum nitride, silicon carbide, magnesia,
4. The electronic circuit board according to any one of the above 1 to 3, which is one or more ceramic fillers selected from alumina).

(5) The electronic circuit board as described in any one of (1) to (3) above, wherein the amount of the filler in the high thermal conductive resin layer is 20 to 85 wt%.

(6) The electronic circuit board as described in any one of (1) to (3) above, wherein the amount of the filler in the filling resin is 20 to 85% by weight.

(7) The electronic circuit board as described in any one of (1) to (6) above, wherein the high thermal conductive resin layer is a high thermal conductive resin film.

(8) A first wiring circuit <306> is laminated and integrated on both sides of the resin substrate <301>, and the substrate <301>
> On the inner surface of the via hole <302>
In the electronic circuit board on which the conductive film <303> for conducting the wiring circuit <306> is formed, the hole portion <302> on the inner surface of the conductive film <303> of the via hole has a high thermal conductive and electrically insulating ceramic filler. (1) filling a resin in which the via hole vacancy <302> is filled with the resin, and a first heat-conductive and electrically insulating ceramic filler mixed on the electronic circuit board filled with the resin. Resin layer <30
7 (1)> is laminated and integrated in a B-staged state, and the first resin layer <307 (1)> has a high thermal conductivity on one side of a metal foil <308>. Second resin layer mixed with conductive and electrically insulating ceramic filler <30
7 (2)>, the resin film side of the laminated body of the metal foil and the B-staged resin film having the structure in which the laminate is integrated and laminated, and pressure-bonded.
(3) heating to bond and cure the first resin layer <307 (1)> and the second resin layer <307 (2)>;
(4) forming the second wiring circuit <308> by etching the metal foil; and the first wiring circuit <306>.
A step (5) of drilling a communication hole between the first wiring circuit and the second wiring circuit <308>, and forming a conductive layer by plating on the inner surface of the drilled communication hole; And a step (6) for electrically connecting the second wiring circuit <308> to the second wiring circuit <308>, and the steps (1) to (6) are sequentially repeated to make the wiring circuit multilayer. A method for manufacturing a circuit board. (See Fig. 3)

(9) The first resin layer <307 (1)>
The method of bonding and curing the first resin layer and the second resin layer <307 (2)> is a method of successively pressing and heating the first resin layer and the second resin layer from one end and heating to bond and cure. Item 8
3. The method for producing a multilayer wiring board according to item 1. (See Fig. 3)

(10) The method of manufacturing an electronic circuit board according to the above item 9, wherein the method of successively pressing the rolls sequentially from one end is roll <309> pressure bonding. (See Fig. 3)

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, each component of the electronic circuit board of the present invention and each step of the method of manufacturing the electronic circuit board of the present invention will be described in detail (see FIGS. 1 to 3). [Step 1: Configuration of Insulating Base] A first wiring circuit (generally, a copper wiring circuit) is laminated and integrated on a resin base, and wiring circuits on both sides of the substrate are electrically connected to inner surfaces of via holes penetrating the substrate. A conduction film for conducting the electric current is formed. Current,
Insulating base materials for circuit boards include glass epoxy, phenolic resin, BT resin, polyimide resin, and insulating base materials consisting of hybrid base materials of ceramics and organic materials. These resins are usually combined with glass fibers. Used in the form of so-called fiber reinforced resin. As the insulating substrate of the present invention, all of these commonly used substrates can be used as they are. The insulating base material of the present invention is formed by laminating and integrating a resin layer having electrical insulation and high thermal conductivity on both sides using the fiber-reinforced resin substrate as a core material.
Also, the inner surface vacancy of the conductive film formed on the inner surface of the via hole is filled with an electrically insulating resin having high thermal conductivity, and the filled resin and the conductive film are sealed and bonded.

In the first step of the present invention, pores on the inner surface of the conductive film are filled with a resin mixed with an electrically insulating ceramic filler having high thermal conductivity. The electrically insulating and high heat conductive resin is a resin base material such as an epoxy resin, a phenol resin, a BT resin, and a polyimide resin mixed with an electrically insulating and high heat conductive ceramic filler. Here, the filler is a powder or a fibrous aggregate.

[0017] Ceramics are generally very low expansion in comparison to resins. Therefore, when a ceramic filler is mixed with a resin, the mixed resin has a significantly low linear expansion coefficient.

Almost all ceramic powders and fibers can be used as long as they are electrically insulating and have high thermal conductivity. Aluminum nitride, silicon carbide, magnesia, alumina, boron nitride, diamond, and the like can be used as appropriate. Particularly, aluminum nitride, silicon carbide, magnesia, and alumina are preferable. These powders and fibers can be used alone or, if necessary, in a mixture of two or more. In addition, other than these, for example, fused silica, mullite, cordierite, zircon, alumina titanate,
Zirconia, spinel, chromia, and the like, or composite ceramics thereof, may be used by mixing as appropriate for the purpose of adjusting the expansion coefficient.

Note that it is necessary that the conductive film and the electrically insulating and high heat conductive resin filling the pores of the conductive film are bonded to each other. If the resin is not bonded, the reinforcing effect on the conductive film does not occur. The filled resin reinforces the mechanical strength of the conductive film and can resist the tensile stress acting on the conductive film. The thermal expansion coefficient of the filled resin is preferably equal to or less than the thermal expansion coefficient of the insulating substrate, and more preferably equal to or less than the thermal expansion coefficient of the conductive film. If the thermal expansion characteristic of the filling material exceeds the thermal expansion coefficient of the insulating substrate, the effect of the filler suppressing the expansion of the conductive film against the elongation of the substrate does not occur. Further, when a material having a thermal expansion coefficient equal to or less than the thermal expansion coefficient value of the conductive film is selected as the filling material, a compressive reinforcing stress always acts on the conductive film, so that cracks do not occur. This crack suppression effect is effective not only for the conductive film but also for the insulating substrate, and suppresses cracks at the glass fiber interface and cracks in the solder resist. In addition, it effectively acts to eliminate the warpage of the substrate.

[Step 2] A resin layer (hereinafter referred to as a first resin layer) in which a high thermal conductive and electrically insulating ceramic filler is mixed on one or both sides of an electronic circuit board serving as a base layer in which via holes are filled with the above resin. (Completely cured) without being cured and stopped in a semi-cured B-stage state, and then laminated and integrated.

The composition of the resin having high electrical conductivity and high thermal conductivity to be laminated on both sides or one side of the electronic circuit board serving as the base layer, and the resin having high electrical conductivity and high thermal conductivity to be filled in the via holes of the insulating base material are as follows. A composition in which an insulating and high thermal conductive ceramic filler is mixed in an amount of 20 to 85 wt% is preferable. If it is less than the lower limit, sufficient heat conductivity cannot be obtained, so that heat diffusion and heat dissipation are not sufficient. On the other hand, exceeding the upper limit is not preferable because the resin becomes brittle. The resin to be filled and the resin to be laminated on the circuit board need not always be the same. It is sufficient that at least the ceramic filler has the above composition range.

The thickness of the electrically insulating and high thermal conductive first resin layer to be laminated on the electronic circuit board serving as the base layer is 20 to 30.
A range of 0 microns is preferred. If it is less than the lower limit, sufficient heat dissipation cannot be obtained. In addition, even if it exceeds the upper limit, the heat dissipation only slightly increases, and thickening causes cost increase,
Not economic. The layer may be formed by applying a resin paste having the above composition, or may be formed into a film and attached thereto. When sticking to a film, use epoxy resin as the base material, mix it with a ceramic filler and process it into a sheet. B-stage (semi-cured) and make the adhesive surface tacky (adhesive) It is preferable to use a method in which the substrate is superposed on the surface of the electronic circuit board of the base layer and cured by heating.

In the present invention, the resin layer having electrical insulation and high thermal conductivity is formed on both sides of the core material. The point is that the core material and the resin layer have different linear expansion coefficients on only one side. I will. By bonding to both surfaces, the warpage is eliminated. Also, by sticking on both sides,
The heat of the front spreads well to the back surface through the highly thermally conductive filling resin of the via hole, so that excessive heating can be prevented.

[Step 3] An electrically insulating, highly thermally conductive resin layer (hereinafter referred to as a second layer) having a composition in which 20 to 85 wt% of an electrically insulating, highly thermally conductive ceramic filler is mixed and in a B-stage state. Of a metal foil (copper foil) and a resin layer having a structure in which a metal layer (generally referred to as a resin layer) is laminated on one side of a metal foil (generally a copper foil). Next, the B-staged second resin layer side is overlapped with the first resin layer prepared in the above step 2 and pressed and heated to bond and cure the first resin layer and the second resin layer.

[Step 4] The metal foil (copper foil) on the surface of the second resin layer is etched to form a second wiring circuit.

[Step 5] A communication hole is formed between the first wiring circuit and the second wiring circuit. Drilling is preferably performed by a CO ₂ gas laser with the wiring circuit 1 positioned after accurate positioning.

[Step 6: Formation of Conductive Film] An electrically conductive film is formed on the inner surface of the drilled communication hole by plating. Although a copper plating film is usually used for the conductive film, not only copper but also a metal film used for ordinary applications of this kind, such as nickel, cobalt, gold, and silver, can be applied. The conductive film is not limited to a single metal film, and may be a laminated film of different metals. In addition, if the metal fine powder of copper, gold, silver, nickel, etc. is mixed with the above-mentioned resin base material, the adhesion strength of the plating film is improved. The powder may be mixed with the above-mentioned insulating base material.

The above-mentioned [Step 1] to [Step 6] are sequentially repeated to form a multilayered wiring circuit.

When a single-layer or multi-layer wiring circuit is further laminated on a wiring circuit formed on an insulating base material with an insulating film interposed therebetween, that is, in the build-up method, the via hole becomes a hole. Therefore, it is necessary to avoid this part and stack the layers. In many cases, wiring circuits cannot be stacked at high density due to the presence of holes. In the present invention, the pores on the inner surface of the conductive film on the inner surface of the via hole are filled with a resin having electrical insulation and high thermal conductivity, and a metal foil (copper foil) is laminated and bonded on the filled resin. Therefore, the wiring circuit can be densely stacked on the holes. The first and second resin layers have a coefficient of thermal expansion of 9 to 9.
Since the expansion is as low as about 10 × 10 ⁻⁶ , the adhesion to the laminated copper circuit is improved, and the reliability against peeling is improved. Incidentally, the peel strength when a conventional insulating base material is used is about 1.2 kg, and in the present invention, 1.6 to 1.8 kg.
To improve. Reliability is improved with high-density mounting.

[0030]

【Example】

Example 1 Electronic circuit board serving as a base material: 27 mm × 27 mm ×
A glass epoxy substrate with a thickness of 0.6 mm is used as a core material, and a 30 μm epoxy resin film, also B-staged, is laminated on both sides of the core material, and an 18 μm copper foil is further laminated on the epoxy resin film. Thermocompression bonded. Composition of epoxy resin film: 7 ceramic fillers mixed at a ratio of 80 aluminum nitride and 20 alumina
0%, 30% epoxy resin composition. The thickness of the film is 30 μm. The adhesive surface of the epoxy resin film was made tacky to make it easy to stick. After the pressing, the copper foil was etched to form a first wiring circuit. After forming the wiring circuit, 248 through holes of φ0.23 mm were drilled. Incidentally, the thermal expansion coefficient of each layer of the wiring board was as follows. Thermal expansion coefficient of epoxy resin film: (13-17) ×
^10-6 Glass epoxy substrate core material Thickness direction (Z direction) 80-100 × 10 ^-6 X direction 13-15 × 10 ^-6 Y direction 13-15 × 10 ^-6 Formation of conductive film Electroless copper on inner surface of via hole A 16 micron copper coating was formed by plating. [Step 1] Next, a filler having the following composition was filled in the inner surface pores of the conductive film. Filler composition (trade name Hysole CB01)
5) Epoxy adhesive 18 wt% (including curing agent) Ceramic filler 82 wt% Composition of ceramic filler: aluminum nitride 80%,
Alumina 20% Thermal expansion coefficient of filler X, Y, Z directions 10-1
After filling the via hole with 3 × 10 ⁻⁶ filler, the material was cured by heating to 180 ° C. for 2 hours. [Step 2] Insulating and high thermal conductive resin having the following composition
Was applied to the height of the wiring circuit on the first copper wiring circuit on both sides of the substrate, and was heated to 70 ° C. for 8 hours to be semi-cured, thereby forming a B stage. [Step 3] Manufacture of laminate of copper foil and B-staged resin film A 20 μm copper foil mixed with an epoxy resin film having the following composition mixed with a ceramic filler is pressed, heated to 70 ° C., and semi-cured (B stage) I let it. Next, the B-stage surface of the epoxy resin is superimposed on the semi-cured resin surface (both surfaces) in step 2, pressed (at a pressure of 2.5 kg / cm ² ), and heated at 150 ° C.
For 40 minutes to complete cure. [Step 4] A copper wiring on both sides was etched to form a second wiring circuit. [Step 5] Using a CO ₂ gas laser, the second wiring circuit and the first wiring circuit
Communication holes were drilled between the wiring circuits. [Step 6] The inner surface of the communication hole is formed by electroless copper plating to be 20
Circuits 1 and 2 were electrically conducted by forming a micron copper coating. Thereafter, the operations of [Step 1] to [Step 6] were repeated three times to produce a circuit board having a total of seven laminated layers.

[Characteristics] Comparison of Mounting Density Compared to the case of bypassing the conventional via hole,
The mounting density of about three times was obtained. Thermal fatigue test A heat cycle of −65 ° C. × 30 minutes to −155 ° C. × 30 minutes was repeated 2000 times. The warpage of the substrate was less than 20 microns. Water pressure test A water pressure test of 121 ° C. and 2 atm was performed. It is improved by about 95% or more compared to the conventional structure bypassing the via hole. Next, the section of each via hole was cut to examine the state of occurrence of cracks. There were no cracks in the plating layer on the inner surface of each via hole. No crack was observed at the glass fiber interface of the base glass epoxy. By the way, in the conventional wiring board which is not filled with the filler, cracks occur in the conductive film in about 80% of the via holes and cracks occur in the glass fiber interface in about 95% of the via holes. Also, the substrate was hardly warped.

Heat dissipation test. In a normal circuit board, a heat sink is mounted below the LSI and a heat spreader is further mounted below the heat sink. In this example, the heat spreader was omitted and used for actual use. There was no significant difference in the temperature rise during actual use compared to the conventional product, and it could be used without any hindrance. It was confirmed that the present invention can be actually used without the heat spreader.

Comparison of Manufacturing Cost The manufacturing cost of the structure of the present invention can be reduced to about half as compared with the conventional multilayer substrate having a structure bypassing the via hole.

[0034]

【The invention's effect】

1. The generation of cracks at the interface between the conductive film on the inner surface of the via hole and the glass fiber of the substrate material can be prevented. 2. The heat dissipation and heat diffusion of the substrate are extremely excellent. 3. High-density mounting is possible because circuits can be formed on via holes. 4. The manufacturing process is simple and the defect rate is extremely low. 5. Low production cost. 6. Extremely fast throughput.

[Procedure amendment]

[Submission date] October 3, 1997

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Brief description of drawings

[Correction method] Added

[Correction contents]

[Brief description of the drawings]

FIG. 1 is an explanatory view of the structure of an electronic circuit board of the present invention.

FIG. 2 is an explanatory diagram of a structure of an electronic circuit board of the present invention.

FIG. 3 is an explanatory view of a method for manufacturing an electronic circuit board according to the present invention.

[Description of Signs] 101: Insulating base material 102: Via hole
103: Conductive film 104: Core material 105: High thermal conductive resin layer 201: Resin substrate 202: Via hole
203 ... conductive film 204 ... core material 205 ... high thermal conductive resin layer 206 ... wiring circuit 207 ... insulating layer 208 ... wiring circuit 301 ... resin substrate 302 ... via hole
303: conductive film 306: wiring circuit 307 (1): resin layer 307 (2): resin layer 308: metal foil 309: roll

Claims (10)

[Claims] 1. An electronic circuit board having a conductive film formed on an inner surface of a via hole penetrating an insulating base material, wherein the insulating base material has a high thermal conductive and electrically insulating filler on both surfaces of a core material made of fiber reinforced resin. It has a structure in which the mixed high thermal conductive resin layer is laminated and integrated, and the pores on the inner surface of the conductive film are mixed with an electrically insulating filler with high thermal conductivity, and are as low as the metal of the conductive film. An electronic circuit board, which is filled with a high thermal conductive resin having a thermal expansion characteristic, and the filled resin and a conductive film are bonded. 2. An electronic circuit board comprising a resin substrate, on which wiring circuits are laminated and integrated on both surfaces, and a conductive film formed on an inner surface of a via hole penetrating the substrate to conduct the wiring circuits on both surfaces. The pores on the inner surface of the film are filled with a high thermal conductive resin having high thermal conductivity, an electrically insulating filler mixed with an electrically insulating filler, and a low thermal expansion property equal to or less than the metal of the conductive film. In addition, one or more multilayer wiring circuits are laminated and integrated on the wiring circuit with an insulating layer interposed therebetween, and the laminated circuit is deposited on the sealed hole. An electronic circuit board, characterized in that: 3. An electronic circuit board comprising: a resin substrate having wiring circuits laminated and integrated on both surfaces thereof; and a conductive film formed on an inner surface of a via hole penetrating the substrate to conduct the wiring circuits on both surfaces. The substrate has a structure in which a high thermal conductive resin layer in which a high thermal conductive and electrically insulating filler is mixed is laminated and integrated on both surfaces of a core material made of a fiber reinforced resin, and the pores on the inner surface of the conductive film have high heat. A conductive and electrically insulating filler mixed with an electrically insulating material, and filled and sealed with a high thermal conductive resin having a low thermal expansion property equal to or less than the metal of the conductive film, and the wiring circuit has A single or multilayer wiring circuit is laminated and integrated with an insulating layer on top,
An electronic circuit board, wherein the laminated circuit is deposited on the closed hole. 4. The high thermal conductive and electrically insulating filler according to claim 1,
The electronic circuit board according to any one of claims 1 to 3, which is one or more ceramic fillers selected from (aluminum nitride, silicon carbide, magnesia, and alumina). 5. The electronic circuit board according to claim 1, wherein the amount of the filler in the high thermal conductive resin layer is 20 to 85 wt%. 6. The amount of the filler in the filling resin is 20 to 20.
The electronic circuit board according to claim 1, wherein the content is 85 wt%. 7. The electronic circuit board according to claim 1, wherein said high thermal conductive resin layer is a high thermal conductive resin film. 8. An electronic circuit board in which first wiring circuits are laminated and integrated on both surfaces of a resin substrate, and a conductive film for conducting the first wiring circuits on both surfaces is formed on an inner surface of a via hole penetrating the substrate. (1) filling a hole in the conductive film inner surface of the via hole with a resin mixed with an electrically insulating ceramic filler having high thermal conductivity; and an electronic circuit board having the via hole filled with the resin. (2) laminating and integrating a first resin layer mixed with a high thermal conductive and electrically insulating ceramic filler in a B-stage state on the first resin layer; The resin film side of a laminate of a metal foil and a B-staged resin film having a structure in which a second resin layer mixed with a high thermal conductive and electrically insulating ceramic filler is laminated and integrated on one surface of the metal foil, Laminate, crimp and heat the first tree A step of bonding and curing the layer and the second resin layer (3); a step of etching the metal foil to form a second wiring circuit (4); the first wiring circuit and the second wiring A step (5) of drilling a communication hole between the circuits, and a step of forming a conductive layer on the inner surface of the drilled communication hole by plating to electrically connect the second wiring circuit and the first wiring circuit ( 6) A method of manufacturing a multilayer electronic circuit board, wherein the steps (1) to (6) are sequentially repeated to multilayer the wiring circuit. 9. The method according to claim 9, wherein the first resin layer and the second resin layer are bonded.
9. The method for manufacturing a multilayer wiring board according to claim 8, wherein the method of curing is a method of successively pressing and heating the first resin layer and the second resin layer from one end, and heating and bonding the first resin layer and the second resin layer. 10. The method for manufacturing a multilayer wiring board according to claim 9, wherein the method of sequentially and sequentially pressing from one end is roll pressing.